Editing variant picker text for product page

[OctaneApparelCo]

I'm hoping I can explain this properly.

Currently the text that is displayed on my website's variant picker for a product is 'Size', with a drop down box for a customer to choose a size.

I want to add a piece of text after the word 'size' which says '(please order one size up)' as the sizing is a little smaller. I've added this as a note all over the product page but customers are still ordering hoodies that are too small.

Now here's where it gets annoying. I want this to only apply to the template I use for the hoodies, and not other templa caps, T-shirts, etc. 

If anyone can help with this, that'd be amazing. Thanks!

[WalkYourStyle]

One idea is to go the products that you want to have one size up and change the 'Size' variants to be +1.

[OctaneApparelCo]

It's not a bad idea. But since the current warnings are still causing issues, I'm worried that'd be too subtle to prevent the issue further.